Refrigerating apparatus



J. R. HORNADAY REFRIGERATING APPARATUS Filed Nov. 22, 19:59A

May ll,` 1943.

fm m 'tion Patented May ll, 1943 REFRIGEBATING APPARATUS` James E.HornadamDayton. Ohio, assignor to General Motors Corporation;corporation of Delaware Dayton, Ohio, a

Application November 22, 1939, Serial No.l 305,701

14 claims.l (ci. 257-8) This invention relates to refrigeratingapparatus and particularly to a refrigerating system for use on arailway car and for similar installations.

One object of this invention isto provide a compact system whichrequires a minimum amount of attention from time to time.

Another object of this invention is to provide a refrigerating systemwhich is capable of maintaining the` temperature within the car within anarrow temperature range.

Still another object of this invention is to provide a system which doesnot excessively dry the air.

the waste heat from the refrigerating system may be utilized intempering the air for the car. Y

A further object oi this invention is to provide a refrigerating systemwhich is flexible in opera.-

electrical controls or complicated valve mecha.- nisms.

A further object of this invention is to provide improved means forcontrolling the temperature within the machinery compartment.

Further objects and advantages of the present invention will be apparentfrom the following description, reference being had to the accompanyingdrawing. wherein avpreferred form of the present invention is clearlyshown.

In the drawing:

Fig. 1 is a sectional elevational view showing the arrangement of therefrigerating apparatus within the air conditioning compartment; and

Fig. 2 is a sectional view taken at right angles to the view shown inFig. 1.

In designing a refrigerating system for use on railway cars, it isimportant to provide a refrigerating system which requires a minimumamount of attention since no one is in regular attendance and the systemis required to operate for long periods of time without any specialservicing. Refrigerating systems of the type disclosed herein arelikewise suitable for use in establishments where service facilities aremeager and the available service men are not suiiiciently trained toservice Vcomplicated systems.

For purposes of illustration, I have shown a refrigerating systemembodying features of my in- 'vention installed in a railway car II)having an air conditioning compartment I2 located at the one end of thecar. As shown in Fig. 1, a machinery compartment I4 has been providedwithin the air conditioning compartment. This machinery compartment iscompletely sealed oif from the rest of 'the air conditioning compart-Another object is to provide a system in which but which does not employany complicated A ating system shown ment so as to prevent the escape ofany oil or gas fumes vfrom the machinery compartment into the main aircirculating system.

Air from the storage compartment II enters the air conditioningcompartment through the opening I6 adjacent the top of the car and ilowsin the direction of the arrows as indicated in Fig. 2; After enteringthe main air conditioning compartment I2, the air circulates in thermalexchange relationship with the refrigerant evaporator I8 and is thenpicked up by the blower 20 which discharges the airinto plenum chamber22 from which the air returns to the storage compartment II through thedischarge opening 24 adjacent the bottom of the car. While I have shownthe intake opening at the top of the car and the discharge opening atthe bottom of the car, it is to be understood that this arrangement isshown primarily for purposes of illustration and that these openings may.be arranged in any conventional manner so as to meet the lar needs ineach installation.

'I'he refrigeratlng system comprises the evaporator I8, the compressor26, a main condenser 28, an auxiliary condenser 30 and a liquidrefrigerant receiver 32. The compressor 26 withdraws the vaporizedrefrigerant from the evapodischarges the compressed refrigerant vapor toarranged in parallel for a hereinafter, and the liquid refrigerantcondensed by these condensers flows into the liquid receiver 32 fromwhich the liquid refrigerant flows through the pipe 34 into theevaporator I8. The usual form of control valve 3 is provided forcontrolling the flow offrefrlgerant to the evaporator. The compressor 26is driven by means of a Diesel engine 38 or its equivalent which alsooperates the blower 2li-as well as the blower 40 which circulatesoutside air through the machinery compartment I4. The Diesel engine 38is provided with a conventional starter 42 which may be manuallyenergized since in the refrigerthe engine is normally operatedcontinuously without'automatic on and off cycling. While therefrigeration may be con- I particupurpose to be described lthe blowerdi) through an outlet 56 also a1'- ranged in the side wall of the car.For purposes of illustration, the opening 56 has been shown as beinglocated directly above the air intake opening 5t; however, this openingmay be arranged to discharge the air underneath the car,v at the top ofthe car or at the side opposite the opening t.

In order to control the amount of cooling air circulated through theengine compartment i4, a damper E8 has been provided for the opening Eiland a by-pass opening 60 has been provided whereby a portion or all vofthe air circulated by the blower 60 may be recirculated through themachinery compartment so as to conserve on the amount of heat dissipateddirectly to the exterior of the car. A damper 62 has been provided inthe opening 8U for controlling the by-passing or recirculation of theair. The arrangement of the dampers 58 and 62. is such that the damper62 is fully closed when the damper 58 is open and,

the damper 5i? is fully closed when the damper p2 is fully open. Bothdampers are operated in unison by means of the thermostatic element 6dwhich, for purposes of illustration has been shown mounted directlywithin the machinery compartment id. The thermostatic element 615 couldbe arranged directly within the compartment il or in any one of the airstreams depending upon the particular conditions which it is desired tocontrol. Ii. desired, the thermostat 64 could be replaced by means oi acontrol responsive to the refrigerant pressure. The thermostat Si!operates the pivoted lever G5 which has the flexible damper cable 38connected to it at the one end. The thermostat Sil operates against thespring 68, the tension of which may be adjusted by the thumb screw 'I8.

As shown in the drawings, the condenser 3l), the engine radiator 52 andthe engine muiiler 12 are all disposed in a heating chamber 'lilprovided in the upper portion of the air conditioning compartment i2.When cooling alone is desired, the heating compartment 75 is completelyclosed o from the compartments l i and I2 by means of the dampers 1B andl which are arranged at the inlet and outlet openings respectively ofthe heating compartment 1B. In order to control the flow of air throughthe heating compartment "i4, I have provided a thermostat 80 within thecompartment il which controls the dampers 16 and It as well as a damper82 arranged in the opening It. As shown in Fig. 2, the dampers 18 and 18are closed when the damper 82 is open, and as the dampers 16 and 78 areopened the damper 82 moves to the closed position. Each of the dampersshown in the system isy biased to the position in which the damper isshown in the drawing. 4The thermostat 80 is adjusted by means of theadjusting screw 84 so as to operate the dampers to cause circulation ofair over the heating elements in the event that it is necessary to heattheair in the car. I

Attention is called to the fact that with the arrangement shown, theDiesel engine is intended to operate at all times. It is also intendedto have all of the air circulated by the blower 20 to too hot forcooling purposes.

pass over the evaporator I8 at all times regardless of the temperaturewithin` the space li. Inasmuch as the Diesel engine never stops, acertain amount of refrigeration will at all times be supplied by theevaporator I 8. However, at such times when the air from the compartmentIl circulates through the heating compartment it before circulating overthe evaporator I8, the eiect will be to heat the air for the compartmentrather than cooling the air for the compartment since heat dissipated bythe engine 38 is added to the air. Y

It will be observed that the condenser 30 is mounted above the condenser28 and that the condensers are arranged in parallel without any controlvalves for controlling the flow to the condensers. By virtue of thearrangement shown, either or both of the condensers may be used forcondensing refrigerant depending upon the ternperature of the airflowing over the respective condensers. When no fresh air is introducedinto the compartment I4 the air therein will become Considering, forexample, the condition under which the damper 58 is fully closed and thedampers 'I6 and 'i8 are fully opened, the condenser 3i) will serve tocondense the maj or portion of the refrigerant whereby-the heat absorbedby the evaporator i8 will be dumped back into the air stream flowingover the evaporator I8. By virtue of the fact that the radiator 52 isdisposed above the radiator 50 a very similar effect is obtained as withthe evaporators in that the radiator 52 will dissipate most, if not all,of the heat given on by the engine. at all times when the relativelycool air from the compartment li circulates over the radiator 52 and nooutside air is circulated over the radiator 28.

The system described hereinabove is especially suitable for use inrefrigerated freight cars since the arrangement of the elements is suchthat a minimum amount of moisture is removed from the air. During theheating period, for example. the air is rst circulated through theheating compartment and is thereafter circulated over the evaporator soas to give up aportion of its heat. However, the temperature of the airpassing over the evaporator is suiciently high to prevent any greatamount of condensation forming on the evaporator coils during the timeheating is required. In installations in which the removal of moisturewould be desirable, the air would first be circulated over theevaporator and then over thecondenser.

For purposes of illustration, the control instru. ments have all beenshown as being responsive to the dry bulb temperature. However, it is tobe understood that other types of controls such as wet bulb instruments,humidostats, effective temperature responsive instruments, and the likemay be substituted for the dry bulb instruments, if desired.

While I have shown the evaporator i8 mounted in the air passage directlyabove the fan 20, it 1s apparent that the evaporator might also belocated adjacent the outlet from the compartment 22, No attempt has beenmade in this application to show any Ventilating means for introducingfresh air into the conditioned space. However, any of the well-knownVentilating means may be used in combination with the system describedhereinabove.

While the form of embodiment of the invention 4 evaporator, means forcirculating outside air over Y a second of said condensers, andtemperature responsive means for controlling the flow of outside airover said second condenser.

2. In a refrigerating system, an evaporator, a plurality of condensersarranged in parallel, a

compressor, refrigerant flow connections betweensaid evaporator,compressor and condensers, means for circulating a stream of air to beconditioned in thermal exchange relationship with one of said condensersand thereafter with said evaporator, means for circulating outside airover a second of said condensers, and temperature responsive means forcontrolling the flow of outside air over said second condenser, saidlast namedv means being responsive to the temperature of the airsurrounding said second condenser.

3. In a refrigerating system, an evaporator, aplurality of condensers, acompressor, refrigerant flow. connections between said evaporator,compressor and condensers, means for circulating a stream of air to beconditioned in thermal exchange relationship with one of said condensersthereafter with said evaporator, and means for circulating outside airover a second of said condensers and means for varying the amount of airflowing over one of said condensers.

4. In a refrigerating system, an evaporator, a plurality of condensers,a compressor, refrigerant ow connections between said evaporator,compressor and condensers, means for circulating a stream of air to beconditioned'in thermal exchange relationship with one of said condensersand thereafter with said evaporator, means for circulating outside airover a second of said condensers, and means for varying the capacity ofone of said condensers.

5. yIn combination, an evaporator, a compressor, a condenser,refrigerant flow connections between said evaporator, compressorand'condenser.. an internal combustion engine for operating saidcompressor, means for circulating a stream of air to be conditioned inthermal exchange with said evaporator, means operated by said engine forcirculating a stream of outside air in thermal exchange with saidcondenser and said internal combustion engine, means for dischargingwaste engine heat into said first named stream of air while said firstnamed stream of air is being cooled by said evaporator, means inuencedby the temperature of the conditioned alr'controlling the speed of saidengine, and temperature responsive means for 'controlling theflow of airover said condenser.

6. Gas conditioning apparatus comprising in combination, means forming agas conditioning chamber, an evaporator in said chamber, a heatdissipator in said chamber, means for circulatengine in said lastnamedchamber for supplying liquid refrigerant to said evaporator, meansfor discharging heat from said refrigerant liquefying apparatus to saidheat dissipator, means for circulating a cooling fluid in thermalexchange with said refrigerant liquefying apparatus, means for varyingthe speed of said engine, and means for varying the amount of heatabsorbed by said last named fluid.

7. In combination, means forming a gas conditioning chamber, anevaporator in said chamber, a heat dissipator in said chamber, means forcirculating gas over said heat dissipator vand thereafter over saidevaporator, means for bypassing said gas around said heat dissipator,means forming a refrigerant liquefying chamber, refrigerant liquefyingapparatus in said Alast named chamber for supplying liquid refrigerantto said evaporator, means for discharging heat from said refrigerantliquefying apparatus to said heat dissipator, means for circulating acooling fluid in thermal exchange with said refrigerant liquefyingapparatus, means for controlling the operation of said liquefyingapparatus, and means for controlling the amount of heat absorbed by saidlast named fluid, said refrigerant after over said second heatexchanger, means for ing a stream of gas through said chamber, meansliquefying apparatus comprising a compressor and an internal combustionengine for operating said compressor.

8. In combination, means forming a gas conditioning chamber, anevaporator in said chamber, a heat dissipator in said chamber, means forcirculating a str eam of gasv through said chamber, means for by-passingsaid gas around said heat dissipator, means forming a refrigerantliquefying chamber, refrigerant liquefying apparatus in said last namedchamber for supplyingv liquid refrigerant to said evaporator, means fordischarging heat from said refrigerant liquefying apparatus to said heatdissipator, means for circulating `a cooling fiuid -in thermal exchangewith said refrigerant liquefying 'apparatus, means controlling theoperation of said apparatus, and means for controlling the amount ofheat absorbed by said last named uid.

9. Air conditioning apparatus for an enclosure comprising incombination, an air fiow passage, first and second heat exchangersarranged in said passage, means for circulating air to -be conditionedover said first heat exchanger and theresupplying liquid refrigerant tothe second of said heat exchangers, means for withdrawing refrigerantvaporized in said second heat exchanger and discharging the same underpressure into the first of said heat exchangers, means responsive to thetemperature within said enclosure for bypassing the air around one ofsaid heat exchangers, and means controlling the amount of heatdischarged by said first heat exchanger.

10. In combination, an evaporator, refrigerant liquefying apparatus forsupplying liquid refrigerant to saidevaporator comprising a compressor,a condenser and an internal combustion engine for operating saidcompressor, means forming an air duct within which said evaporator islocated, means enclosing said refrigerant liquefying apparatus, liquidcirculating means for transferring heat generated by said apparatusevaporator.

11. In combination,. an evaporator, refrigerant liquefying apparatus forsupplying liquid refrigerant to said evaporator comprising a compressor,a condenser and an internal combustion engine for operating saidcompressor, means iform-l 5 ing an air duct within which said evaporatoris located, means enclosing said refrigerant liquei'ying apparatus,liquid circulating means for `transferring' heat generated by saidapparatus of air for said compartment in thermal exchange with saidevaporator; refrigerant liqueiying apparatus for supplying liquidrefrigerant to said evaporator; means for circulating a second stream ofair in thermal exchange with said refrigerant liquefying apparatus; saidrefrigerant liquefying apparatus comprising means for circulating a heattransfer iiuid in thermal exchange with said first and second streams ofair and said liquefying apparatus for heating said first named stream ofair before the air is cooled by said evaporator; means for controllingthe ow of air over said liquefying apparatus; and temperature responsivemeans for controlling the operation of said refrigerant liquefyingmeans.

13. In combination, a iirst heat exchanger adapted to function as anevaporator for absorbfing heat; a second heat exchanger adapted tofunction as a condenser for dissipating a portion of the heat absorbedby said iirst heat exchanger, a third heat exchanger adapted to functionas a condenser for dissipating a portion of the heat absorbed by saidfirst heat exchanger. a compressor for withdrawing refrigerant from saidfirst heat exchanger and discharging said refrigerant into another ofsaid heat exchangers, an internall combustion engine for energizing saidcompressor, means for flowing a medium to be ,conditioned in thermalexchange with said first and second named heat exchangers, means for ocirculating a stream of uid in thermal exchange with said internalcombustion engine and said third named heat exchanger, means forregulating the temperature of the fluid circulated in thermal exchangewith said engine, and temperature responsive means for controlling theflow of fluid over said engine.

14. In combination, an evaporator, a compressor, a'condenser,refrigerant iiow connections between said evaporator, compressor andcondenser, an internal combustion engine for operating said compressor,means for circulating a stream oi' air to be conditioned in thermalexchange with said evaporator, means for circulating a separate streamof outside air in thermal exchange with said condenser and said internalcombustion engine, and liquid circulating means for discharging wasteengine heat directly into said flrst named air stream before the air iscirculated over said evaporator so as to modify the cooling anddehumidifying effect of said evaporator.

JAMES R. HORNADAY.

